Unitek 6-099-04, Operation And Maintenance Manual

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CHAPTER 1: SYSTEM DESCRIPTION
MICROPULL
®
IV WIRE BOND PULL TESTER
1-14 990-180
Beam Drive Module (figures 1-1 and 3-4)
Zero Adjustment - The output of the strain gauge preamplifier can be re-zeroed by slowly turning the
four-turn screwdriver adjustable potentiometer, accessible through the top of the beam module cover,
until the minus sign on the PEAK FORCE display just goes out. This control may be set to +0.3% of
full scale with the ZERO switch in the MAN position (out). The switch can then be set to AUTO (in)
and used without further adjustment.
Site Illumination
-
The intensity of the site illumination lamp can be changed by using the
ILLUMINATION control (located on the front panel of the Electronic Control Unit). The bulb is a T-
3.25, 12 volt, miniature bayonet lamps (GE 1891); UMC part number 435-047.
Test Status Indicator
- The red Test Status Indicator indicates the following:
a. Each time a new test is initiated by pressing the footswitch, this lamp will light and will remain
lit until the PRESET FORCE is reached or the HOLD TIME expires and the hook returns to the
downstop.
b. When blinking, it indicates that the beam has hit the Upstop - the result of either excessive loop
height, the hook slipping from the bond, or a bond which broke at less than 4% of full scale.
c. When extinguished, it indicates the completion of a Non-Destruct test.
d. When lit in the Non-Destruct Mode, the footswitch is inhibited.
The bulb is a red T-3.25, 12 volt, miniature bayonet lamps (UMC part number 4-29441-01).